Vertical falling film type heat exchangers and like equipment have long been in use. In such equipment, a plurality of vertically disposed condenser tubes is mounted between upper and lower headers. Fluid is introduced into the condenser tubes from their upper ends, and a distributor device is utilized in each condenser tube to distribute the fluid and help it form a falling film on the interior surface of the tube. The fluid film then falls downwardly on the condenser tube interior surface into a fluid collection area beneath the lower header.
There can be many hundreds of condenser tubes in a typical heat exchanger or the like, and all of the tubes must be fitted with a fluid distributor device. Typically, the condenser tubes will be mounted so that the upper ends thereof all open into an upper header which contains a body of fluid, the fluid being allowed to flow by gravity into the tubes.
In certain types of equipment, the quality of the hollow cylindrical fluid film on the interior surfaces of the vertical condenser tubes is not too critical. However, in other instances it is necessary that the condenser tube interior surfaces be completely and evenly wetted at all times. For example, in a standard brine concentrator, which may contain 1800 or more vertical condenser tubes into which a brine slurry flows to form the falling fluid film, it is necessary that all portions of the tube interior surfaces be completely and continuously wetted. Otherwise, scale can form on the tube interior surfaces, and can accumulate until the condenser tubes become blocked and the heat exchanger is rendered inoperable.
A number of fluid distributor devices has been proposed over the years, which for purposes of this discussion can be divided into two general types. One type is shown in U.S. Pat. No. 3,995,663, wherein a tapered or other suitably shaped fluid distributing member is centrally mounted by one or more struts within the bore of a distributor body. While this type of distributor can produce effective results, the distributing member and its supporting struts tend to abrade during usage, especially when the operating fluid is a brine slurry or the like. Further, the distributing member and its supporting struts tend to capture any foreign matter in the fluid, which can cause blockage of the fluid flow and the formation of an incomplete falling film.
In the second general type of distributor device, to which this invention relates, the distributor member and its supporting struts are eliminated. Instead, the fluid is introduced tangentially into a chamber in the distributor body to form a swirling vortex, and the vortex places a rotating, hollow cylindrical film of fluid on the interior surface of the condenser tube. An example of a fluid distributor device of this type is shown in U.S. Pat. No. 3,016,067.
The device of U.S. Pat. No. 3,016,067 shows, in FIGS. 3 and 4, a distributor having an open frustoconical chamber with a flat top wall. Fluid is introduced into the upper end of this chamber through horizontally disposed passageways, arranged tangentially to the frusto-conical chamber wall. Fluid entering the chamber swirls about to establish a vortex, and forms a rotating, uniform hollow cylindrical fluid film on the interior surface of a vertical condenser tube connected with the distributor. The present invention is an improvement on the distributor of U.S. Pat. No. 3,016,067 and produces a most even wetting of the condenser tube's interior surface.